Question

When Bradshaw and colleagues investigated the quantitative trait loci (QTL) of two species of Mimulus (Mimulus cardinalis and Mimulus lewisii), they used marker loci as a way to map the QTLs. Their results are shown in the accompanying figure. According to these results, ________.

1) the differences in genotype for the majority of these QTLs explained small amounts of the variations in flower phenotypes for both species

2) some of the QTLs did have pronounced effects on the flowers' phenotypes

3) at least one QTL explained 90% of the phenotypic variance for each species

4) All of the above.

Answer 1

The investigation showed that some of the QTLs had pronounced effects on the flowers' phenotypes.

Step-by-step explanation:

The results of Bradshaw and colleagues' investigation on the quantitative trait loci (QTL) of Mimulus species showed that some of the QTLs had pronounced effects on the flowers' phenotypes, indicating that they contribute significantly to the variation in flower traits. However, the differences in genotype for the majority of these QTLs explained small amounts of the variations in flower phenotypes for both species. Therefore, the correct answer is option 2) some of the QTLs did have pronounced effects on the flowers' phenotypes.